Some people print a conversion chart and post it conveniently in the kitchen, or near a desk.
After a while, you can move easily between metric and US or Imperial, even without a scale (which is, of course, a useful thing to have around).
For example,
http://startcooking.com/measurement-and-conversion-charts

Shuna is a pastry chef in New York City and author of the acclaimed blog Eggbeater.

added almost 3 years ago

I use a few different methods for converting metric to Imperial.

1. Guesstimate. One pound = 454 grams, so 100g chocolate is about four ounces, etc.
2. One ounce = 28.35 grams.
3. Google or I love the app Smart Chef for conversions
4. Most liquids are listed as ml as well as ounces
5. A $30 digital scale can toggle between grams and ounces - it's great to see what grams "look like."

I will plug metric here. Cups and ounces do not help people bake better. it's so easy to add or remove 10% of 100, than 1/3C. As well, 1/3C of sugar does not weigh the same as 1/3C of flour, etc. Seeing that all recipes are really ratios helps cooks expand beyond "the recipe" into spontaneous, inventive territories.